Expandable wiper system

Abstract

A vehicle window wiper system includes a wiper arm having a sliding joint operated by a linear actuator which selectively extends and retract the sliding joint. A controller is configured to cause the linear actuator to selectively extend and retract the sliding joint. A wiper arm rotational position provided to the controller determines whether the wiper arm should be in an extended or a retracted position.

What is claimed: 
     
       1. A vehicle window wiper system, comprising a wiper arm comprising a sliding joint having a linear actuator operatively connected to a controller and including a biasing member and a linear solenoid arranged to selectively extend and retract the sliding joint;
 wherein the controller selectively causes the linear actuator to extend and retract the sliding joint between a normal operating mode and an extended operating mode according to a plurality of inputs including a window wiper motor torque value, a window wiper motor shaft rotational speed value, and a wiper arm position relative to a vehicle window perimeter. 
 
     
     
       2. The system of  claim 1 , wherein the wiper arm position is determined by determining a rotational angle of the wiper arm. 
     
     
       3. The system of  claim 1 , wherein the wiper arm position is determined by an imager. 
     
     
       4. The system of  claim 3 , wherein the imager is an on-board camera disposed to capture images of at least a portion of the vehicle window. 
     
     
       5. The system of  claim 1 , wherein the wiper arm position is determined by a potentiometer. 
     
     
       6. A vehicle window wiper system, comprising:
 a wiper arm comprising a sliding joint having a linear actuator operating to selectively extend and retract the sliding joint; and 
 a controller operatively connected to the linear actuator, configured to cause the linear actuator to selectively extend and retract the sliding joint; 
 wherein the controller selectively causes the linear actuator to extend and retract the sliding joint between a normal operating mode and an extended operating mode according to a plurality of inputs including a window wiper motor torque value, a window wiper motor shaft rotational speed value, and a wiper arm position relative to a vehicle window perimeter. 
 
     
     
       7. The system of  claim 6 , wherein the wiper arm position is determined by determining a rotational angle of the wiper arm. 
     
     
       8. The system of  claim 6 , wherein the wiper arm position is determined by an imager. 
     
     
       9. The system of  claim 8 , wherein the imager is an on-board camera disposed to capture images of at least a portion of the vehicle window. 
     
     
       10. The system of  claim 6 , wherein the wiper arm position is determined by a potentiometer. 
     
     
       11. The system of  claim 6 , wherein the linear actuator comprises a biasing member and a linear solenoid arranged to selectively extend and retract the sliding joint. 
     
     
       12. The system of  claim 6 , wherein the linear actuator comprises a hydraulic or pneumatic piston which operates to selectively extend and retract the sliding joint. 
     
     
       13. A vehicle window wiper system, comprising:
 a wiper arm comprising a sliding joint having a linear actuator operating to selectively extend and retract the sliding joint; 
 a controller operating to cause the linear actuator to selectively extend and retract the sliding joint according to a wiper arm position relative to a vehicle window perimeter; and 
 a potentiometer arranged to provide the wiper arm position to the controller; 
 wherein the controller selectively causes the linear actuator to translate the sliding joint between a normal operating mode and an extended operating mode according to a plurality of inputs including a window wiper motor torque value, a window wiper motor shaft rotational speed value, and the wiper arm position. 
 
     
     
       14. The system of  claim 13 , wherein the linear actuator comprises a biasing member and a linear solenoid arranged to selectively extend and retract the sliding joint. 
     
     
       15. The system of  claim 13 , wherein the linear actuator comprises a hydraulic or pneumatic piston which operates to selectively extend and retract the sliding joint.